/*
 * Copyright 2018 Qunar, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package qunar.tc.qmq.store;

import java.text.NumberFormat;

/**
 * @author keli.wang
 * @since 2017/7/3
 */
final class StoreUtils {
    static String offset2FileName(final long offset) {
        final NumberFormat nf = NumberFormat.getInstance();
        nf.setMinimumIntegerDigits(20);
        nf.setMaximumFractionDigits(0);
        nf.setGroupingUsed(false);
        return nf.format(offset);
    }

    static String offsetFileNameForSegment(final LogSegment segment) {
        return offsetFileNameOf(segment.getBaseOffset());
    }

    static String offsetFileNameOf(final long baseOffset) {
        return "." + StoreUtils.offset2FileName(baseOffset) + ".offset";
    }
}
